Anti-gravity belts were repulsorlift devices which allowed individuals to simulate flight, rising many, many meters above the ground. Luke Skywalker and Leia Organa used the devices on the planet Skye during their attack on Kharys. Coupled with winged disguises, the two Humans resembled native S'kytri, enabling them to surprise Kharys' Imperial forces. It's possible that this device may be similar or identical to the grav-belt used by Jediboh Opera performers.